Report - typed carbon copy - 31 foolscap sheets with three graphs and drawings within a brown card folder bound with adhesive tape and fold back clips. Titled "Tramcar Sound Levels - External", dated 30/3/1950, prepared by the MMTB Testing Department, Report No. N1/1/38. Gives details of the purpose of the test, procedures, results, discussion and conclusions. Includes various classes of trams (including W3 and W4 class trams), appendices with sound levels, location plan for testing. Testing done on ballasted track in St Georges Road. Signed by D. H. Eakins. Two copies held.trams, tramways, preston workshops, reports, specification, wheels, tramcars, track, noise